Hi Justin, Thanks for replying. There is a reason why I don't want to create a consumer per broker/instance of artemis. I am trying to come up with an architecture for a product where an artemis cluster can expand or shrink but it shouldn't have any impact on client code.
Considering the suggested approach, client code has to be updated according to the size of the cluster. So, I was thinking, could this be possible that client can connect to any of the broker and then messages could be routed because consumers might not always be online. Consumers can connect once in a while. This case becomes especially important, while upgrading clusers. Regards, Prateek Jain -------------------------------------------------------------- EXPECTATION : Causes all troubles...... -------------------------------------------------------------- On Mon, Apr 10, 2023 at 4:39 PM Justin Bertram <jbert...@apache.org> wrote: > While it's true that with ON_DEMAND you don't get the same behavior as > STRICT (as one would expect), you still get the benefit of load-balancing > because messages will be initially distributed to nodes that have > consumers. This is why it's called "on demand" - messages are distributed > to where the consumers are rather than strictly round-robined across all > cluster nodes. > > You can achieve 1, 2, & 3 with ON_DEMAND and a redistribution-delay > 0 > [1]. This is the most common configuration. > > That said, clustering is all about increasing overall message throughput > via horizontal scaling. In order to optimize performance you really don't > ever want to move messages between nodes as that adds latency. You want > every node in the cluster to have enough consumers to process all the > messages sent to that node. If that's not the case that's an indication > that the cluster is, in fact, too large and you're wasting resources. I > recently added a new section to the cluster documentation [2] discussing > this very thing. > > > Justin > > [1] > > https://activemq.apache.org/components/artemis/documentation/latest/clusters.html#message-redistribution > [2] > > https://github.com/apache/activemq-artemis/blob/main/docs/user-manual/en/clusters.md#performance-considerations > > On Fri, Apr 7, 2023 at 7:51 AM prateekjai...@gmail.com < > prateekjai...@gmail.com> wrote: > > > Hi Roskvist, > > > > I tried the ON_DEMAND value but still it doesnt work. Infact, with > > on_demand value the loadbalancing stops and the whole scalability feature > > in the cluster becomes irrelevant. > > > > IMO, if the client for a queue/topic is connected to any of the broker > > instances then; messages should get routed to it. So, in nutshell; what I > > am trying to achieve here is - > > > > 1. Deploy cluster in such a way that it should be easy to scale. > > 2. Scalability should be transparent to the client code. Clients should > > only know about broker IPs and Ports. > > 3. A Client should be able to send and receive messages w/o taking into > > consideration; to which broker they are connected to. > > > > I am able to achieve most of them. It is only the receiving part which is > > not working as desired. In the clustered queue example, something very > > similar is achieved but it requires, client to be connected to both > > instances. But in my case, I am trying to achieve it by connecting to any > > instance (live) in the cluster. > > > > Regards, > > Prateek > > > > > > On Fri 7 Apr 2023, 12:56 Roskvist Anton, <anton.roskv...@volvo.com> > wrote: > > > > > Right, so as far as I am aware the STRICT load balancing policy does > not > > > allow for message redistribution, it's purpose is to divide incoming > > > messages evenly across the cluster regardless of client/consumer state. > > > Perhaps ON_DEMAND might be better suited for your needs, or possibly > > > OFF_WITH_REDISTRIBUTION and handling initial distribution of messages > via > > > client side load balancing? > > > > > > ________________________________ > > > > > > This email message (including its attachments) is confidential and may > > > contain privileged information and is intended solely for the use of > the > > > individual and/or entity to whom it is addressed. If you are not the > > > intended recipient of this e-mail you may not disseminate, distribute > or > > > copy this e-mail (including its attachments), or any part thereof. If > > this > > > e-mail is received in error, please notify the sender immediately by > > return > > > e-mail and make sure that this e-mail (including its attachments), and > > all > > > copies thereof, are immediately deleted from your system. Please > further > > > note that when you communicate with us via email or visit our website > we > > > process your personal data. See our privacy policy for more information > > > about how we process it: https://www.volvogroup.com/en-en/privacy.html > > > > > >
